In vitro study of magnetite-amyloid β complex formation

Biogenic magnetite (Fe3O4) has been identified in human brain tissue. However, abnormal concentration of magnetite nanoparticles in the brain has been observed in different neurodegenerative pathologies. In the case of Alzheimer's disease (AD), these magnetic nanoparticles have been identified attached to the characteristic brain plaques, which are mainly formed by fibrils of amyloid β peptide (Aβ). However, few clues about the formation of the magnetite-Aβ complex have been reported. We have investigated the interaction between these important players in AD with superconducting quantum interference, scanning electron microscope, surface plasmon resonance, and magnetic force microscopy. The results support the notion that the magnetite-Aβ complex is created before the synthesis of the magnetic nanoparticles, bringing a highly stable interaction of this couple.From the Clinical EditorThis paper describes the association of magnetite nanoparticles and Aβ in vitro. Given the number and impact of neurodegenerative diseases associated with β amyloid deposition, future in vitro and in vivo applications are expected to lead to an enhanced understanding of these important and as of yet generally incurable diseases.

Graphical AbstractAbnormal concentration of magnetite nanoparticles in the brain has been observed in different neurodegenerative pathologies. In the case of Alzheimer's disease (AD), these magnetic nanoparticles have been identified attached to the fibrils of amyloid β peptide (Aβ). However, few clues about the formation of the magnetite-Aβ complex have been reported. This work represents a first approach to study the association of magnetite nanoparticles and Aβ in vitro.Iron can adopt both the ferric (Fe3+) and ferrous (Fe2+) valence states in vivo. The ability to change from one state to the other confers a very important role on iron in different biological oxidation and transport processes. However, the disruption of the normal iron metabolism can entail harmful consequences because Fe3+ and, especially, Fe2+ generate toxic free radicals mainly via the Fenton reaction.Figure optionsDownload high-quality image (196 K)Download as PowerPoint slide